Title :
On Frequency Domain Doppler Diversity Using Basis Expansion Model and EM-Based Algorithms in CDMA Systems
Author :
Wang, Tianqi ; Li, Cheng ; Chen, Hsiao-Hwa ; Guizani, Mohsen
Author_Institution :
Memorial Univ. of Newfoundland, St. John´´s
Abstract :
In this paper, we propose an algorithm for frequency domain adaptive Doppler shift estimation in the presence of multiple Doppler subpaths in DS-CDMA systems. By modeling doubly selective channel with a basis expansion model (BEM), the proposed method works based on expectation-maximization (EM) algorithm and can accurately estimate Doppler shifts. A complete Cramer-Rao lower bound (CRLB) analysis of the estimation algorithms is also provided.
Keywords :
Doppler shift; code division multiple access; optimisation; spread spectrum communication; Cramer-Rao lower bound; DS-CDMA systems; Doppler diversity; Doppler shifts; adaptive Doppler shift estimation; basis expansion model; expectation maximization; frequency domain; Algorithm design and analysis; Computer science; Councils; Doppler shift; Fading; Frequency domain analysis; Frequency estimation; Multiaccess communication; Multipath channels; RAKE receivers;
Conference_Titel :
Global Telecommunications Conference, 2007. GLOBECOM '07. IEEE
Conference_Location :
Washington, DC
Print_ISBN :
978-1-4244-1042-2
Electronic_ISBN :
978-1-4244-1043-9
DOI :
10.1109/GLOCOM.2007.842
